1. Field of Invention
The invention relates to a portable refrigerator unit cooled by a thermoelectric element of the Peltier type having hot and cold faces adapted to be energized by an external DC source, and adapted to be disconnected from said unit to make the unit entirely portable, and to a method for transporting food to picnic areas.
2. Prior Art
It is well known in the art that a heating and cooling effect can be produced by impressing a DC voltage across a thermoelectric element of the Peltier type, and this effect has been utilized for cooling the interior of a portable refrigerator or other surface. Such applications of thermoelectric elements of the Peltier type, for example, are found in, among others, U.S. Pat. Nos. 3,314,242, 3,230,723, 3,220,198, 3,194,023, 3,178,896, 3,168,816, 3,018,631, and 3,048,020. Such devices, however, have complicated structures for conducting heat to the cold face of the thermoelectric unit and thereafter conducting heat from the hot face thereof to the ambient atmosphere. Moreover, in all these units, the power pack is an integral part of the unit, so that the unit is not entirely portable. Also, none of these units have an internal thermal sink firmly imbedded in an insulated wall of the unit with an external thermal sink secured thereto and maintaining the thermoelectric element in compression between the two thermal sinks. None of the prior art devices shows a simple and effective portable refrigeration unit which can, for example, be energized by an automobile or boat battery while traveling, and disconnected therefrom in order to take the unit to a picnic area.